1. Field of the invention
The present invention relates to a keylockable buckle of the type made of synthetic resin and comprising a plug and a socket adapted to be coupled together, the plug having a cantilevered presser flap on its upper surface which is yieldable downwardly to bring the plug out of coupling engagement with the socket, and particularly relates to a buckle of the type described which can be locked in coupled disposition by a separate key for the purpose of security or burglarproofness.
2. Description of prior art
As commonly known, a buckle of the kind described is very simple in construction and easy to handle because only depression of the presser flap brings a plug out of coupling engagement with a socket. This type of buckle, therefore, is of very wide application, for example, in baggages, knapsackes, and the like. However, for easiness in handling, the conventional buckle has a drawback that it cannot be used on a container, a baggage etc. which are likely to be transported by many and unspecified carriers and are thus liable to robbery.
In these circumstances, there have been proposed recently some buckles for security purpose. A typical buckle of this type has a locking slide plate slidably mounted on a cantilevered presser flap. Sliding the locking slide plate rearwardly on the presser flap causes an abutment provided on the lower surface of the locking slide plate to come into abutting engagement with a rear wall of the buckle, thus bringing the presser flap out of operation so that the plug and socket are locked in coupled disposition.
However, in this convention buckle, by only sliding the locking slide plate forwardly, the presser flap becomes operative so that the buckle is uncoupled and the contents of the baggage is accessible. So, this buckle is unsatisfactory as well.